During pregnancy, as part of the antenatal blood test, your hepatitis B status will be checked. If you test positive for hepatitis B, you will be offered a test that checks the level of hepatitis B virus in your blood. The level of hepatitis B is called the viral load. Without treatment, the higher your viral load, the greater the chance of passing the hepatitis B virus to your baby.
- If your viral load is high, then the risk of transmission of the hepatitis B virus to your baby is >90%.
- If your viral load is low, then the risk of transmission of the hepatitis B virus to your baby is between 30–50%.
There are various medicines that can reduce the risk of transmission of the virus to 0% and protect your baby from hepatitis B.
- All babies born to mothers with hepatitis B will be given hepatitis B vaccine and hepatitis B immunoglobulin soon after delivery.
- However, if your viral load is high, you will also be offered treatment with an antiviral medicine called tenofovir to reduce the amount of virus in your body before delivery.
Tenofovir tablet is an antiviral medicine. Tenofovir stops the hepatitis B virus multiplying, thereby stopping the virus crossing the placenta to infect your baby. This tablet is taken for the last 8–12 weeks of pregnancy (the third trimester) and is continued for 4–12 weeks after your baby is born. Tenofovir is safe for you and your baby, and you can breastfeed while taking it. Read more about tenofovir.
Hepatitis B vaccine and hepatitis B immunoglobulin
Soon after delivery, your baby will be given 2 injections: a dose of the hepatitis B vaccine and a dose of hepatitis B immunoglobulin.
- Your baby will also need the usual hepatitis vaccine at 6 weeks, 3 months and 5 months of age. Read more about the hepatitis B vaccine.
- At 9 months of age, your baby will be given a blood test to check whether they are protected against hepatitis B or have been infected with the virus. If your baby is not protected, a further 2 doses of the hepatitis B vaccine may be given.
What are the side effects of the vaccine and immunoglobulin?
Like all medicines, hepatitis B vaccine and hepatitis B immunoglobulin can cause side effects, although not everyone gets them. Some of the possible side effects include a mild reaction to the injection such as a rash or a rise in body temperature and, rarely, a severe reaction to the injection.